Maximum User-Expandable Storage
Expandable Storage Capacity is the documented maximum music storage a user can add inside a server. It is separate from the capacity installed at the factory.
Keep the stated basis with the number: a limit per bay is not automatically a total across every bay.
Maximum User-Expandable Storage — Music Server
For a music server, this figure helps you plan a larger local library. Check compatible drive size, interface and installation procedure as well as capacity. A physically fitting drive may still fall outside the supported configuration.
Compare the additional storage allowed, not a total that combines a factory drive with an expansion slot. If a maximum refers to a replacement drive, preserve that condition too. External USB drives and network shares are separate storage routes.
A vacant bay does not establish an unlimited capacity, and no stated maximum means unknown rather than zero. Expansion capacity also does not guarantee backup or redundancy; plan protection for the enlarged library separately.